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Protocell formation on micrometeorites
Abstract We report on the formation of membranous protocells by self-assembly of lipids on micrometeorites, the extraterrestrial particles that have been continuously reaching the surface of the Earth ever since its formation. Synergistic interactions of lipid compartments with pristine extraterrestrial surfaces are entirely unexplored, but constitute a possible scenario for early evolution of primitive cells by a surface energy-driven transformation mechanism. Lipids utilize the surface energy of the particles to adhere to them and autonomously transform into spherical compartments, typically through formation of lipid nanotubes. Natural sand particles of similar composition and shape were simultaneously investigated for reference, showing that certain lipid compositions prefer micrometeorite surfaces. The elemental composition of the particles, their surface texture and cleanness altogether may be contributing to the differences observed in lipid behavior. Lipid nanotubes on- and extending out of- the micrometeorites were observed to carry lipid particles and connect to other objects in the surrounding environment.
Assessing the accuracy of ChatGPT responses to caregiver questions in pediatric neurology: an observational study
Application of the integrated geophysical methods on the Zhalageamu copper-polymetallic deposit, Inner Mongolia, China
Evolutionary characteristics and driving mechanisms of the spatial association network of carbon unlocking in the Yangtze River Delta urban agglomeration
A Cognitive Theory of Reasoning and Choice
Abstract We present a theory of choice in which attention to the features of options is determined by the decision maker’s categorization of the current problem in a set of problems she solved in the past. Categorization depends on goal-relevant and contextual problem-level features. The model yields heterogeneity in attention and choice in a given problem based on different past experiences and instability when changes in irrelevant context cause recategorization. We show that heterogeneous and unstable representations of a choice problem unify major biases in judgment and decision making.
Surface induced investigation of the chemical composition of end-of-life magnets with GD-OES for the development of efficient recycling strategies
Abstract Glow discharge optical emission spectroscopy (GD-OES) was investigated as a rapid characterization method for End-of-Life (EoL) neodymium-iron-boron (NdFeB) permanent magnets to support recycling-oriented sorting and process selection. The method was applied to analyze the coating systems, near-surface contamination, and bulk material composition of EoL magnets originating from different application fields. Close attention was placed on the use of radio-frequency GD-OES (RF-GD-OES), a variant of GD-OES that enables the investigation of electrically non-conductive materials and coatings, making it suitable for the analysis of epoxy-coated EoL magnets. Various coating systems commonly found on EoL magnets, including epoxy coatings, zinc (Zn) coatings, multilayer system of nickel, copper and nickel (Ni/Cu/Ni), were successfully identified by RF-GD-OES. In addition to determining the elemental composition of the coating layers, the method enabled the determination of coating thicknesses through depth profiling. The obtained layer structures and coating thicknesses were compared with cross-sectional SEM investigations. An overlay of GD-OES depth profiles with SEM cross-sectional images demonstrated good agreement, indicating that GD-OES provides consistent information on coating architecture and layer thicknesses. Furthermore, the technique proved suitable for detecting oxygen- and carbon-rich surface regions associated with corrosion and contamination, as well as for identifying magnets treated by grain boundary diffusion (GBD) processes. To enable the assessment of rare earth element contents, an internal semi-quantitative calibration approach was developed for neodymium (Nd), dysprosium (Dy), and praseodymium (Pr). Compared with conventional characterization methods such as SEM/EDXS cross-sectional analysis, GD-OES requires significantly less sample preparation and provides rapid access to both elemental depth distributions and light-element information, including carbon, oxygen, and boron. The results demonstrate the potential of RF-GD-OES as an efficient characterization tool for the assessment and recycling-oriented sorting of EoL NdFeB magnets.
Business, Liquidity, and Information Cycles
Abstract Stock markets play a dual role: they provide information about firms’ fundamentals, which improves resource allocations, and they provide liquidity. We propose a setting in which these two roles interact: if stocks are used more intensively for liquidity, then prices reveal less information about fundamentals. We structurally estimate stock price informativeness for several countries and show that it declines when alternative liquidity sources, such as banks, are in distress. To study the real effects of this mechanism, we devise a strategy to integrate our stock-trading module into a dynamic general equilibrium model with heterogeneous firms. We calibrate the model to the United States and simulate recessions with and without banking distress. In a standalone recession, prices become more informative and allocation improves, mitigating output losses by 4.4%. If the recession coincides with banking distress, agents rely more on stock markets to obtain liquidity, prices become less informative, and allocation deteriorates, magnifying output losses by 22%.
Self-regulated learning and perfectionism as predictors of listening anxiety in the context of foreign language learning
Public Services Under Private Management
Abstract Theory predicts that outsourcing public services to the private sector can reduce costs and improve efficiency but can also induce cost-cutting and compromise quality. We assess the Brazilian Organizações Sociais de Saude model (OSS), which outsources management of public hospital services to the private sector while the state remains the residual claimant. We show that this enhances hospital production and operational efficiency without adverse effects on hospital quality and equity. Increased inpatient production addresses previously unmet demand, expanding local access to hospital care and reducing population mortality. Performance gains arise from improved operational efficiency achieved through increased hospital management capacity. This facilitates staffing adjustments, favoring higher-skilled personnel, dismissing lower-productivity staff, and adopting flexible, performance-tied employment contracts. Effects are larger among private organizations with more management experience, underscoring returns to managerial capacity. Our findings show that incentive-ownership structures can address the quantity-quality trade-off in public service delivery, even when contracts are incomplete and quality is hard to measure.
A hybrid CNN-BiLSTM approach for predicting the purchase behavior of customers in e-commerce
The Power of Proximity to Coworkers
Abstract How does proximity to coworkers affect training and productivity? We study software engineers at a Fortune 500 firm from 2019 to 2024, leveraging two shocks to proximity: the office closures in 2020 and the subsequent return-to-office mandates in 2022 and 2023. In both cases, co-located teams experienced bigger changes in proximity than distributed ones, facilitating difference-in-differences designs. We find that sitting near teammates increases coding feedback by 18.3% and improves code quality. Gains are concentrated among less-tenured and younger employees, who are building human capital. However, there is a trade-off: experienced engineers write less code when sitting near teammates. In national U.S. data, we find evidence that the rise of remote work has had scarring effects on young college graduates. In remotable jobs, young graduates’ unemployment rate increased relative to older graduates’ post-pandemic (2022–2024) compared to pre-pandemic (2017–2019), a pattern we do not observe in non-remotable jobs.
Aging and aggregation enhance antibiotics persistence and sequestration on polyethylene microplastics
International Reserve Management Under Rollover Crises
Abstract This article investigates how a government should manage international reserves when it faces the risk of a rollover crisis. We ask: Should the government accumulate reserves or reduce debt to make itself less vulnerable? We show that the optimal policy entails initially reducing debt, followed by a subsequent increase in both debt and reserves as the government approaches a safe zone. Furthermore, we find that issuing additional debt to accumulate reserves can lead to a reduction in sovereign spreads. Evidence from a panel of emerging economies is consistent with these predictions: increases in reserves financed by public external borrowing are associated with lower spreads, and reserve holdings are not systematically drawn down during crisis episodes.
Self- and examiner perspective of visual functioning in orientation and mobility of older adults living in residential care homes in Croatia
Praying for Rain
Abstract We study rainmaking as an instrumental religious belief. We present a model in which a religious leader tries to persuade people to believe. Praying for rain can persuade only where the hazard of rainfall during a dry spell is increasing over time, so that prayer is most likely to succeed when people most want rain. We present evidence from prayers for rain in Murcia, Spain, where the hazard rate is increasing, that the church’s prayers for rain predict rainfall over two centuries. To generalize this finding, we gather an original data set of whether ethnic groups around the world traditionally prayed for rain. We find that ethnic groups facing an increasing rainfall hazard are 47% more likely to pray for rain, consistent with our model’s prediction that societies are more likely to pray for rain where prayer is persuasive.
A 3-D whole-body human thermoregulatory model to simulate extreme cold stress
Abstract Prolonged exposure to Arctic-like conditions can lead to adverse physiological outcomes, significantly affecting the health, performance, and operational readiness of civilians and military personnel. In this study, we extended our previously developed, anatomically realistic, three-dimensional thermoregulatory virtual human model to more comprehensively predict changes in core body temperature and skin temperature of peripheral body regions (dorsum hand, fingertip, face, dorsum foot, and toe-tip) and the cheek under extreme cold-air temperatures down to −40.0 °C and wind speeds ranging from 0.1 to 3.0 m·s −1 . To assess model performance, we computed the root mean square error (RMSE) between model predictions and experimental data as well as the fraction of model predictions that lie within two standard errors of the mean experimental data from eight cold-air exposure studies involving 75 unique subjects. Overall, we observed a reasonable agreement between model predictions and the experimental measurements, with average RMSEs of about 0.2 °C for core body temperature, 0.5 to 1.8 °C for mean skin, 1.6 to 2.7 °C for fingertip, 1.2 to 3.5 °C for toe-tip, and 2.1 to 2.7 °C for cheek skin temperature. As such, the extended model can serve as a valuable tool to inform the development of guidelines to help mitigate the risk of cold-related injuries during prolonged exposures to extreme-cold environments.
Why Doesn’t the United States Have National Health Insurance? The Political Role of the American Medical Association
Abstract This article examines how the American Medical Association (AMA) helped shape the development of the U.S. health insurance system in the critical period after World War II. Working with the political public relations firm Campaigns, Inc., the AMA launched a nationwide campaign to weaken support for national health insurance by framing it as “socialized medicine,” while simultaneously enrolling people in private health insurance plans to shift demand away from a public alternative. Drawing on newly assembled archival data, we find that greater exposure to the campaign explains about 20% of the rise in private health insurance enrollment and a comparable decline in public support for a national program. The campaign also appears to have influenced policy making through coordinated messaging, resolutions passed by civic organizations, congressional rhetoric, and political donations. These findings suggest that the rise of private health insurance in the United States was not solely due to macroeconomic forces or collective bargaining; rather, it was also enabled by a strategic, interest group–financed effort to shape citizen views and influence policy.
A hybrid deep learning and attention fusion framework for intelligent zero-day threat detection in cloud web application firewalls
The Effects of Mandatory Profit-Sharing on Workers and Firms: Evidence from France
Abstract Since 1967, all French firms with more than 100 employees have been required to share a fraction of their excess profits with their employees. Through this scheme, firms with excess profits distribute, on average, 10.5% of their pretax income to workers. In 1990, the eligibility threshold was reduced to 50 employees. We exploit this regulatory change to identify the effects of mandated profit-sharing on firms and their employees. The cost of mandated profit-sharing for firms is evident in the significant bunching at the 100-employee threshold observed prior to the reform, which completely disappears post-reform. Using a difference-in-differences strategy, we find that at the firm level, mandated profit-sharing (i) increases the labor share by 1.8 percentage points, (ii) reduces the profit share by 1.4 percentage points, and (iii) has small to nonexistent effects on investment and productivity. At the employee level, mandated profit-sharing increases lower-skilled workers’ total compensation and leaves high-skilled workers’ total compensation unchanged. Overall, mandated profit-sharing redistributes excess profits to lower-skilled workers in the firm without generating significant distortions or productivity effects.